Humans cannot see all of the light that the sun emits but light detecting, spectroscopic, telescopes can.
This image composite from NASA reveals that hidden light and x-rays radiating from the Sun and its atmosphere.
Image captures like this can help us determine why the Sun’s corona reaches temps in the millions which is 100 times hotter than its surface.
This is odd because sources of heat are typically hotter than the surrounding atmosphere not cooler.
The hotter temps could be caused by small flares of heat, light, and particles that heat the atmosphere.